The long-term objectives of this project are to develop further applications of synthetic polymers and therapeutic devices for preventing and treating eye problems. The principal specific aims are: 1. Fluid-scleral lenses with perfluorocarbons - To evaluate the protection afforded the cornea and conjunctiva by simultaneous use of a gas-permeable scleral contact lens and a viscous oxygen carrier. Thus, this project will attempt to develop a method for protecting and preserving the cornea in severe dry-eye patients; preventing neuroparalytic keratitis, corneal dystrophies, chronic epithelial defects, pemphigoid, and Stevens-Johnson syndrome; and preserving the eye after destruction of the eyelids by burns or other trauma. To achieve these objectives, we will strive to find a suitable viscous liquid perfluorocarbon or chlorofluorocarbon compound (or clear emulsion) that dissolves a large amount of oxygen and is permeable to oxygen. Such a liquid could be used with oxygen-permeable fluid-scleral lenses to maintain the cornea during daily wear. This project involves the interaction of chemistry with ocular toxicology, physiology, and ophthalmology. 2. Vitreous implant - To investigate additional modalities for treating complicated cases or retinal detachment and proliferative vitreoretinopathy, including (a) study of the interaction of silicone and fluorosilicone oils with intraocular tissues, including re-evaluation of the controversial migration of the oils into the retina and other ocular tissues using histologic and scanning electron microscopy and energy-dispersive x-ray analysis, and HPLC analysis of retinol and other retinal lipids in the intraocular oils; (b) development of a long-lasting viteous implant will physiologic properties superior to silicone oil, such as chemically crosslinked hyaluronic acid hydrogels and highly viscous chlorofluorocarbon oils; and (c) study of methods for preventing proliferative vitreoretinopathy with the liposoluble drug BCNU dissolved in the intraocular silicone oil. This research involves the interaction of polymer chemistry, organic chemistry, toxicology, and ophthalmology.